better camera such as Nikon D4s or Canon D1x which have better low light iso performance.

A 7D can delivery very nice images when down sample at the ISO used. It may not look pretty at 1:1, so shoot much tighter in order to put all pixels to work instead of cropping them away. Also, less butts and more faces while keeping the shutter speeds higher (1/400 and 1/640 are very marginal.) Properly exposed ISO-3200 is very usable on the 7D.